Always the sign of a stooge when he can't get takers to do the work. They KNOW it won't work and so won't put in a quote.![]()
So you've still not explained at all how a dpm under the floor will make any difference at all to damp in the walls.
If anything fitting a Dpm under the floor would force any potential ground water under the building sidewsys and into the footings/walls even more, exacerbating the problem further.
I hope to god your not a professional plasterer or if you are I'll have £50 on you being the type flogging drill and inject damp proofing to pensioners.
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